libev/ev.c

#include <math.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>

#include <stdio.h>

#include <assert.h>
#include <errno.h>
#include <sys/time.h>
#include <time.h>

#ifndef HAVE_MONOTONIC
# ifdef CLOCK_MONOTONIC
#  define HAVE_MONOTONIC 1
# endif
#endif

#ifndef HAVE_SELECT
# define HAVE_SELECT 1
#endif

#ifndef HAVE_EPOLL
# define HAVE_EPOLL 0
#endif

#ifndef HAVE_REALTIME
# define HAVE_REALTIME 1 /* posix requirement, but might be slower */
#endif

#define MIN_TIMEJUMP  1. /* minimum timejump that gets detected (if monotonic clock available) */
#define MAX_BLOCKTIME 60.

#include "ev.h"

struct ev_watcher {
  EV_WATCHER (ev_watcher);
};

struct ev_watcher_list {
  EV_WATCHER_LIST (ev_watcher_list);
};

typedef struct ev_watcher *W;
typedef struct ev_watcher_list *WL;

static ev_tstamp now, diff; /* monotonic clock */
ev_tstamp ev_now;
int ev_method;

static int have_monotonic; /* runtime */

static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */
static void (*method_modify)(int fd, int oev, int nev);
static void (*method_poll)(ev_tstamp timeout);

/*****************************************************************************/

ev_tstamp
ev_time (void)
{
#if HAVE_REALTIME
  struct timespec ts;
  clock_gettime (CLOCK_REALTIME, &ts);
  return ts.tv_sec + ts.tv_nsec * 1e-9;
#else
  struct timeval tv;
  gettimeofday (&tv, 0);
  return tv.tv_sec + tv.tv_usec * 1e-6;
#endif
}

static ev_tstamp
get_clock (void)
{
#if HAVE_MONOTONIC
  if (have_monotonic)
    {
      struct timespec ts;
      clock_gettime (CLOCK_MONOTONIC, &ts);
      return ts.tv_sec + ts.tv_nsec * 1e-9;
    }
#endif

  return ev_time ();
}

#define array_needsize(base,cur,cnt,init)               \
  if ((cnt) > cur)                                      \
    {                                                   \
      int newcnt = cur ? cur << 1 : 16;                 \
      fprintf (stderr, "resize(" # base ") from %d to %d\n", cur, newcnt);\
      base = realloc (base, sizeof (*base) * (newcnt)); \
      init (base + cur, newcnt - cur);                  \
      cur = newcnt;                                     \
    }

/*****************************************************************************/

typedef struct
{
  struct ev_io *head;
  unsigned char wev, rev; /* want, received event set */
} ANFD;

static ANFD *anfds;
static int anfdmax;

static int *fdchanges;
static int fdchangemax, fdchangecnt;

static void
anfds_init (ANFD *base, int count)
{
  while (count--)
    {
      base->head = 0;
      base->wev = base->rev = EV_NONE;
      ++base;
    }
}

typedef struct
{
  W w;
  int events;
} ANPENDING;

static ANPENDING *pendings;
static int pendingmax, pendingcnt;

static void
event (W w, int events)
{
  w->pending = ++pendingcnt;
  array_needsize (pendings, pendingmax, pendingcnt, );
  pendings [pendingcnt - 1].w      = w;
  pendings [pendingcnt - 1].events = events;
}

static void
fd_event (int fd, int events)
{
  ANFD *anfd = anfds + fd;
  struct ev_io *w;

  for (w = anfd->head; w; w = w->next)
    {
      int ev = w->events & events;

      if (ev)
        event ((W)w, ev);
    }
}

static void
queue_events (W *events, int eventcnt, int type)
{
  int i;

  for (i = 0; i < eventcnt; ++i)
    event (events [i], type);
}

/*****************************************************************************/

static struct ev_timer **atimers;
static int atimermax, atimercnt;

static struct ev_timer **rtimers;
static int rtimermax, rtimercnt;

static void
upheap (struct ev_timer **timers, int k)
{
  struct ev_timer *w = timers [k];

  while (k && timers [k >> 1]->at > w->at)
    {
      timers [k] = timers [k >> 1];
      timers [k]->active = k + 1;
      k >>= 1;
    }

  timers [k] = w;
  timers [k]->active = k + 1;

}

static void
downheap (struct ev_timer **timers, int N, int k)
{
  struct ev_timer *w = timers [k];

  while (k < (N >> 1))
    {
      int j = k << 1;

      if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
        ++j;

      if (w->at <= timers [j]->at)
        break;

      timers [k] = timers [j];
      timers [k]->active = k + 1;
      k = j;
    }

  timers [k] = w;
  timers [k]->active = k + 1;
}

/*****************************************************************************/

typedef struct
{
  struct ev_signal *head;
  sig_atomic_t gotsig;
} ANSIG;

static ANSIG *signals;
static int signalmax;

static int sigpipe [2];
static sig_atomic_t gotsig;
static struct ev_io sigev;

static void
signals_init (ANSIG *base, int count)
{
  while (count--)
    {
      base->head   = 0;
      base->gotsig = 0;
      ++base;
    }
}

static void
sighandler (int signum)
{
  signals [signum - 1].gotsig = 1;

  if (!gotsig)
    {
      gotsig = 1;
      write (sigpipe [1], &gotsig, 1);
    }
}

static void
sigcb (struct ev_io *iow, int revents)
{
  struct ev_signal *w;
  int sig;

  gotsig = 0;
  read (sigpipe [0], &revents, 1);

  for (sig = signalmax; sig--; )
    if (signals [sig].gotsig)
      {
        signals [sig].gotsig = 0;

        for (w = signals [sig].head; w; w = w->next)
          event ((W)w, EV_SIGNAL);
      }
}

static void
siginit (void)
{
  fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
  fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);

  /* rather than sort out wether we really need nb, set it */
  fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
  fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);

  evio_set (&sigev, sigpipe [0], EV_READ);
  evio_start (&sigev);
}

/*****************************************************************************/

static struct ev_idle **idles;
static int idlemax, idlecnt;

static struct ev_check **checks;
static int checkmax, checkcnt;

/*****************************************************************************/

#if HAVE_EPOLL
# include "ev_epoll.c"
#endif
#if HAVE_SELECT
# include "ev_select.c"
#endif

int ev_init (int flags)
{
#if HAVE_MONOTONIC
  {
    struct timespec ts;
    if (!clock_gettime (CLOCK_MONOTONIC, &ts))
      have_monotonic = 1;
  }
#endif

  ev_now = ev_time ();
  now    = get_clock ();
  diff   = ev_now - now;

  if (pipe (sigpipe))
    return 0;

  ev_method = EVMETHOD_NONE;
#if HAVE_EPOLL
  if (ev_method == EVMETHOD_NONE) epoll_init (flags);
#endif
#if HAVE_SELECT
  if (ev_method == EVMETHOD_NONE) select_init (flags);
#endif

  if (ev_method)
    {
      evw_init (&sigev, sigcb, 0);
      siginit ();
    }

  return ev_method;
}

/*****************************************************************************/

void ev_prefork (void)
{
  /* nop */
}

void ev_postfork_parent (void)
{
  /* nop */
}

void ev_postfork_child (void)
{
#if HAVE_EPOLL
  if (ev_method == EVMETHOD_EPOLL)
    epoll_postfork_child ();
#endif

  evio_stop (&sigev);
  close (sigpipe [0]);
  close (sigpipe [1]);
  pipe (sigpipe);
  siginit ();
}

/*****************************************************************************/

static void
fd_reify (void)
{
  int i;

  for (i = 0; i < fdchangecnt; ++i)
    {
      int fd = fdchanges [i];
      ANFD *anfd = anfds + fd;
      struct ev_io *w;

      int wev = 0;

      for (w = anfd->head; w; w = w->next)
        wev |= w->events;

      if (anfd->wev != wev)
        {
          method_modify (fd, anfd->wev, wev);
          anfd->wev = wev;
        }
    }

  fdchangecnt = 0;
}

static void
call_pending ()
{
  int i;

  for (i = 0; i < pendingcnt; ++i)
    {
      ANPENDING *p = pendings + i;

      if (p->w)
        {
          p->w->pending = 0;
          p->w->cb (p->w, p->events);
        }
    }

  pendingcnt = 0;
}

static void
timers_reify (struct ev_timer **timers, int timercnt, ev_tstamp now)
{
  while (timercnt && timers [0]->at <= now)
    {
      struct ev_timer *w = timers [0];

      /* first reschedule or stop timer */
      if (w->repeat)
        {
          if (w->is_abs)
            w->at += floor ((now - w->at) / w->repeat + 1.) * w->repeat;
          else
            w->at = now + w->repeat;

          assert (w->at > now);

          downheap (timers, timercnt, 0);
        }
      else
        {
          evtimer_stop (w); /* nonrepeating: stop timer */
          --timercnt; /* maybe pass by reference instead? */
        }

      event ((W)w, EV_TIMEOUT);
    }
}

static void
time_update ()
{
  int i;
  ev_now = ev_time ();

  if (have_monotonic)
    {
      ev_tstamp odiff = diff;

      /* detecting time jumps is much more difficult */
      for (i = 2; --i; ) /* loop a few times, before making important decisions */
        {
          now = get_clock ();
          diff = ev_now - now;

          if (fabs (odiff - diff) < MIN_TIMEJUMP)
            return; /* all is well */

          ev_now = ev_time ();
        }

      /* time jump detected, reschedule atimers */
      for (i = 0; i < atimercnt; ++i)
        {
          struct ev_timer *w = atimers [i];
          w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat;
        }
    }
  else
    {
      if (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
        /* time jump detected, adjust rtimers */
        for (i = 0; i < rtimercnt; ++i)
          rtimers [i]->at += ev_now - now;

      now = ev_now;
    }
}

int ev_loop_done;

void ev_loop (int flags)
{
  double block;
  ev_loop_done = flags & EVLOOP_ONESHOT;

  if (checkcnt)
    {
      queue_events ((W *)checks, checkcnt, EV_CHECK);
      call_pending ();
    }

  do
    {
      /* update fd-related kernel structures */
      fd_reify ();

      /* calculate blocking time */
      if (flags & EVLOOP_NONBLOCK || idlecnt)
        block = 0.;
      else
        {
          block = MAX_BLOCKTIME;

          if (rtimercnt)
            {
              ev_tstamp to = rtimers [0]->at - get_clock () + method_fudge;
              if (block > to) block = to;
            }

          if (atimercnt)
            {
              ev_tstamp to = atimers [0]->at - ev_time   () + method_fudge;
              if (block > to) block = to;
            }

          if (block < 0.) block = 0.;
        }

      method_poll (block);

      /* update ev_now, do magic */
      time_update ();

      /* queue pending timers and reschedule them */
      /* absolute timers first */
      timers_reify (atimers, atimercnt, ev_now);
      /* relative timers second */
      timers_reify (rtimers, rtimercnt, now);

      /* queue idle watchers unless io or timers are pending */
      if (!pendingcnt)
        queue_events ((W *)idles, idlecnt, EV_IDLE);

      /* queue check and possibly idle watchers */
      queue_events ((W *)checks, checkcnt, EV_CHECK);

      call_pending ();
    }
  while (!ev_loop_done);
}

/*****************************************************************************/

static void
wlist_add (WL *head, WL elem)
{
  elem->next = *head;
  *head = elem;
}

static void
wlist_del (WL *head, WL elem)
{
  while (*head)
    {
      if (*head == elem)
        {
          *head = elem->next;
          return;
        }

      head = &(*head)->next;
    }
}

static void
ev_start (W w, int active)
{
  w->pending = 0;
  w->active = active;
}

static void
ev_stop (W w)
{
  if (w->pending)
    pendings [w->pending - 1].w = 0;

  w->active = 0;
}

/*****************************************************************************/

void
evio_start (struct ev_io *w)
{
  if (ev_is_active (w))
    return;

  int fd = w->fd;

  ev_start ((W)w, 1);
  array_needsize (anfds, anfdmax, fd + 1, anfds_init);
  wlist_add ((WL *)&anfds[fd].head, (WL)w);

  ++fdchangecnt;
  array_needsize (fdchanges, fdchangemax, fdchangecnt, );
  fdchanges [fdchangecnt - 1] = fd;
}

void
evio_stop (struct ev_io *w)
{
  if (!ev_is_active (w))
    return;

  wlist_del ((WL *)&anfds[w->fd].head, (WL)w);
  ev_stop ((W)w);

  ++fdchangecnt;
  array_needsize (fdchanges, fdchangemax, fdchangecnt, );
  fdchanges [fdchangecnt - 1] = w->fd;
}

void
evtimer_start (struct ev_timer *w)
{
  if (ev_is_active (w))
    return;

  if (w->is_abs)
    {
      /* this formula differs from the one in timer_reify becuse we do not round up */
      if (w->repeat)
        w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;

      ev_start ((W)w, ++atimercnt);
      array_needsize (atimers, atimermax, atimercnt, );
      atimers [atimercnt - 1] = w;
      upheap (atimers, atimercnt - 1);
    }
  else
    {
      w->at += now;

      ev_start ((W)w, ++rtimercnt);
      array_needsize (rtimers, rtimermax, rtimercnt, );
      rtimers [rtimercnt - 1] = w;
      upheap (rtimers, rtimercnt - 1);
    }

}

void
evtimer_stop (struct ev_timer *w)
{
  if (!ev_is_active (w))
    return;

  if (w->is_abs)
    {
      if (w->active < atimercnt--)
        {
          atimers [w->active - 1] = atimers [atimercnt];
          downheap (atimers, atimercnt, w->active - 1);
        }
    }
  else
    {
      if (w->active < rtimercnt--)
        {
          rtimers [w->active - 1] = rtimers [rtimercnt];
          downheap (rtimers, rtimercnt, w->active - 1);
        }
    }

  ev_stop ((W)w);
}

void
evsignal_start (struct ev_signal *w)
{
  if (ev_is_active (w))
    return;

  ev_start ((W)w, 1);
  array_needsize (signals, signalmax, w->signum, signals_init);
  wlist_add ((WL *)&signals [w->signum - 1].head, (WL)w);

  if (!w->next)
    {
      struct sigaction sa;
      sa.sa_handler = sighandler;
      sigfillset (&sa.sa_mask);
      sa.sa_flags = 0;
      sigaction (w->signum, &sa, 0);
    }
}

void
evsignal_stop (struct ev_signal *w)
{
  if (!ev_is_active (w))
    return;

  wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w);
  ev_stop ((W)w);

  if (!signals [w->signum - 1].head)
    signal (w->signum, SIG_DFL);
}

void evidle_start (struct ev_idle *w)
{
  if (ev_is_active (w))
    return;

  ev_start ((W)w, ++idlecnt);
  array_needsize (idles, idlemax, idlecnt, );
  idles [idlecnt - 1] = w;
}

void evidle_stop (struct ev_idle *w)
{
  idles [w->active - 1] = idles [--idlecnt];
  ev_stop ((W)w);
}

void evcheck_start (struct ev_check *w)
{
  if (ev_is_active (w))
    return;

  ev_start ((W)w, ++checkcnt);
  array_needsize (checks, checkmax, checkcnt, );
  checks [checkcnt - 1] = w;
}

void evcheck_stop (struct ev_check *w)
{
  checks [w->active - 1] = checks [--checkcnt];
  ev_stop ((W)w);
}

/*****************************************************************************/

#if 0

static void
sin_cb (struct ev_io *w, int revents)
{
  fprintf (stderr, "sin %d, revents %d\n", w->fd, revents);
}

static void
ocb (struct ev_timer *w, int revents)
{
  //fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
  evtimer_stop (w);
  evtimer_start (w);
}

static void
scb (struct ev_signal *w, int revents)
{
  fprintf (stderr, "signal %x,%d\n", revents, w->signum);
}

static void
gcb (struct ev_signal *w, int revents)
{
  fprintf (stderr, "generic %x\n", revents);
}

int main (void)
{
  struct ev_io sin;

  ev_init (0);

  evw_init (&sin, sin_cb, 55);
  evio_set (&sin, 0, EV_READ);
  evio_start (&sin);

  struct ev_timer t[10000];

#if 0
  int i;
  for (i = 0; i < 10000; ++i)
    {
      struct ev_timer *w = t + i;
      evw_init (w, ocb, i);
      evtimer_set_abs (w, drand48 (), 0.99775533);
      evtimer_start (w);
      if (drand48 () < 0.5)
        evtimer_stop (w);
    }
#endif

  struct ev_timer t1;
  evw_init (&t1, ocb, 0);
  evtimer_set_abs (&t1, 5, 10);
  evtimer_start (&t1);

  struct ev_signal sig;
  evw_init (&sig, scb, 65535);
  evsignal_set (&sig, SIGQUIT);
  evsignal_start (&sig);

  struct ev_check cw;
  evw_init (&cw, gcb, 0);
  evcheck_start (&cw);

  struct ev_idle iw;
  evw_init (&iw, gcb, 0);
  evidle_start (&iw);

  ev_loop (0);

  return 0;
}

#endif


Revision:	1.11
Committed:	Wed Oct 31 07:40:49 2007 UTC (16 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.10:	+2 -1 lines
Log Message:	sugar
#	User	Rev	Content
1	root	1.1	#include <math.h>
2			#include <stdlib.h>
3	root	1.7	#include <unistd.h>
4			#include <fcntl.h>
5			#include <signal.h>
6	root	1.1
7			#include <stdio.h>
8
9	root	1.4	#include <assert.h>
10	root	1.1	#include <errno.h>
11			#include <sys/time.h>
12			#include <time.h>
13
14	root	1.10	#ifndef HAVE_MONOTONIC
15			# ifdef CLOCK_MONOTONIC
16			# define HAVE_MONOTONIC 1
17			# endif
18	root	1.1	#endif
19
20	root	1.10	#ifndef HAVE_SELECT
21			# define HAVE_SELECT 1
22			#endif
23
24			#ifndef HAVE_EPOLL
25			# define HAVE_EPOLL 0
26			#endif
27
28			#ifndef HAVE_REALTIME
29			# define HAVE_REALTIME 1 /* posix requirement, but might be slower */
30			#endif
31	root	1.1
32	root	1.4	#define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */
33	root	1.1	#define MAX_BLOCKTIME 60.
34
35			#include "ev.h"
36
37			struct ev_watcher {
38			EV_WATCHER (ev_watcher);
39			};
40
41			struct ev_watcher_list {
42			EV_WATCHER_LIST (ev_watcher_list);
43			};
44
45	root	1.10	typedef struct ev_watcher *W;
46			typedef struct ev_watcher_list *WL;
47
48	root	1.4	static ev_tstamp now, diff; /* monotonic clock */
49	root	1.1	ev_tstamp ev_now;
50			int ev_method;
51
52			static int have_monotonic; /* runtime */
53
54			static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */
55	root	1.5	static void (*method_modify)(int fd, int oev, int nev);
56	root	1.1	static void (*method_poll)(ev_tstamp timeout);
57
58	root	1.8	/*****************************************************************************/
59
60	root	1.1	ev_tstamp
61			ev_time (void)
62			{
63			#if HAVE_REALTIME
64			struct timespec ts;
65			clock_gettime (CLOCK_REALTIME, &ts);
66			return ts.tv_sec + ts.tv_nsec * 1e-9;
67			#else
68			struct timeval tv;
69			gettimeofday (&tv, 0);
70			return tv.tv_sec + tv.tv_usec * 1e-6;
71			#endif
72			}
73
74			static ev_tstamp
75			get_clock (void)
76			{
77			#if HAVE_MONOTONIC
78			if (have_monotonic)
79			{
80			struct timespec ts;
81			clock_gettime (CLOCK_MONOTONIC, &ts);
82			return ts.tv_sec + ts.tv_nsec * 1e-9;
83			}
84			#endif
85
86			return ev_time ();
87			}
88
89			#define array_needsize(base,cur,cnt,init) \
90			if ((cnt) > cur) \
91			{ \
92	root	1.2	int newcnt = cur ? cur << 1 : 16; \
93	root	1.1	fprintf (stderr, "resize(" # base ") from %d to %d\n", cur, newcnt);\
94			base = realloc (base, sizeof (base) (newcnt)); \
95			init (base + cur, newcnt - cur); \
96			cur = newcnt; \
97			}
98
99	root	1.8	/*****************************************************************************/
100
101	root	1.1	typedef struct
102			{
103			struct ev_io *head;
104			unsigned char wev, rev; /* want, received event set */
105			} ANFD;
106
107			static ANFD *anfds;
108			static int anfdmax;
109
110			static int *fdchanges;
111			static int fdchangemax, fdchangecnt;
112
113			static void
114			anfds_init (ANFD *base, int count)
115			{
116			while (count--)
117			{
118			base->head = 0;
119			base->wev = base->rev = EV_NONE;
120			++base;
121			}
122			}
123
124			typedef struct
125			{
126	root	1.10	W w;
127	root	1.1	int events;
128			} ANPENDING;
129
130			static ANPENDING *pendings;
131			static int pendingmax, pendingcnt;
132
133			static void
134	root	1.10	event (W w, int events)
135	root	1.1	{
136			w->pending = ++pendingcnt;
137			array_needsize (pendings, pendingmax, pendingcnt, );
138			pendings [pendingcnt - 1].w = w;
139			pendings [pendingcnt - 1].events = events;
140			}
141
142			static void
143			fd_event (int fd, int events)
144			{
145			ANFD *anfd = anfds + fd;
146			struct ev_io *w;
147
148			for (w = anfd->head; w; w = w->next)
149			{
150			int ev = w->events & events;
151
152			if (ev)
153	root	1.10	event ((W)w, ev);
154	root	1.1	}
155			}
156
157	root	1.9	static void
158	root	1.10	queue_events (W *events, int eventcnt, int type)
159	root	1.9	{
160			int i;
161
162			for (i = 0; i < eventcnt; ++i)
163			event (events [i], type);
164			}
165
166	root	1.8	/*****************************************************************************/
167
168	root	1.4	static struct ev_timer **atimers;
169			static int atimermax, atimercnt;
170
171			static struct ev_timer **rtimers;
172			static int rtimermax, rtimercnt;
173	root	1.1
174			static void
175	root	1.4	upheap (struct ev_timer **timers, int k)
176	root	1.1	{
177			struct ev_timer *w = timers [k];
178
179			while (k && timers [k >> 1]->at > w->at)
180			{
181			timers [k] = timers [k >> 1];
182			timers [k]->active = k + 1;
183			k >>= 1;
184			}
185
186			timers [k] = w;
187			timers [k]->active = k + 1;
188
189			}
190
191			static void
192	root	1.4	downheap (struct ev_timer **timers, int N, int k)
193	root	1.1	{
194			struct ev_timer *w = timers [k];
195
196	root	1.4	while (k < (N >> 1))
197	root	1.1	{
198			int j = k << 1;
199
200	root	1.4	if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
201	root	1.1	++j;
202
203			if (w->at <= timers [j]->at)
204			break;
205
206			timers [k] = timers [j];
207	root	1.2	timers [k]->active = k + 1;
208	root	1.1	k = j;
209			}
210
211			timers [k] = w;
212			timers [k]->active = k + 1;
213			}
214
215	root	1.8	/*****************************************************************************/
216
217	root	1.7	typedef struct
218			{
219			struct ev_signal *head;
220			sig_atomic_t gotsig;
221			} ANSIG;
222
223			static ANSIG *signals;
224	root	1.4	static int signalmax;
225	root	1.1
226	root	1.7	static int sigpipe [2];
227			static sig_atomic_t gotsig;
228			static struct ev_io sigev;
229
230	root	1.1	static void
231	root	1.7	signals_init (ANSIG *base, int count)
232	root	1.1	{
233			while (count--)
234	root	1.7	{
235			base->head = 0;
236			base->gotsig = 0;
237			++base;
238			}
239			}
240
241			static void
242			sighandler (int signum)
243			{
244			signals [signum - 1].gotsig = 1;
245
246			if (!gotsig)
247			{
248			gotsig = 1;
249			write (sigpipe [1], &gotsig, 1);
250			}
251			}
252
253			static void
254			sigcb (struct ev_io *iow, int revents)
255			{
256			struct ev_signal *w;
257			int sig;
258
259			gotsig = 0;
260			read (sigpipe [0], &revents, 1);
261
262			for (sig = signalmax; sig--; )
263			if (signals [sig].gotsig)
264			{
265			signals [sig].gotsig = 0;
266
267			for (w = signals [sig].head; w; w = w->next)
268	root	1.10	event ((W)w, EV_SIGNAL);
269	root	1.7	}
270			}
271
272			static void
273			siginit (void)
274			{
275			fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
276			fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
277
278			/* rather than sort out wether we really need nb, set it */
279			fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
280			fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
281
282			evio_set (&sigev, sigpipe [0], EV_READ);
283			evio_start (&sigev);
284	root	1.1	}
285
286	root	1.8	/*****************************************************************************/
287
288	root	1.9	static struct ev_idle **idles;
289			static int idlemax, idlecnt;
290
291			static struct ev_check **checks;
292			static int checkmax, checkcnt;
293
294			/*****************************************************************************/
295
296	root	1.1	#if HAVE_EPOLL
297			# include "ev_epoll.c"
298			#endif
299			#if HAVE_SELECT
300			# include "ev_select.c"
301			#endif
302
303			int ev_init (int flags)
304			{
305			#if HAVE_MONOTONIC
306			{
307			struct timespec ts;
308			if (!clock_gettime (CLOCK_MONOTONIC, &ts))
309			have_monotonic = 1;
310			}
311			#endif
312
313			ev_now = ev_time ();
314	root	1.4	now = get_clock ();
315			diff = ev_now - now;
316	root	1.1
317	root	1.7	if (pipe (sigpipe))
318			return 0;
319
320			ev_method = EVMETHOD_NONE;
321	root	1.1	#if HAVE_EPOLL
322	root	1.7	if (ev_method == EVMETHOD_NONE) epoll_init (flags);
323	root	1.1	#endif
324			#if HAVE_SELECT
325	root	1.7	if (ev_method == EVMETHOD_NONE) select_init (flags);
326	root	1.1	#endif
327
328	root	1.7	if (ev_method)
329			{
330			evw_init (&sigev, sigcb, 0);
331			siginit ();
332			}
333
334	root	1.1	return ev_method;
335			}
336
337	root	1.8	/*****************************************************************************/
338
339	root	1.1	void ev_prefork (void)
340			{
341	root	1.11	/* nop */
342	root	1.1	}
343
344			void ev_postfork_parent (void)
345			{
346	root	1.11	/* nop */
347	root	1.1	}
348
349			void ev_postfork_child (void)
350			{
351			#if HAVE_EPOLL
352	root	1.5	if (ev_method == EVMETHOD_EPOLL)
353			epoll_postfork_child ();
354	root	1.1	#endif
355	root	1.7
356			evio_stop (&sigev);
357			close (sigpipe [0]);
358			close (sigpipe [1]);
359			pipe (sigpipe);
360			siginit ();
361	root	1.1	}
362
363	root	1.8	/*****************************************************************************/
364
365	root	1.1	static void
366	root	1.5	fd_reify (void)
367			{
368			int i;
369
370			for (i = 0; i < fdchangecnt; ++i)
371			{
372			int fd = fdchanges [i];
373			ANFD *anfd = anfds + fd;
374			struct ev_io *w;
375
376			int wev = 0;
377
378			for (w = anfd->head; w; w = w->next)
379			wev \|= w->events;
380
381			if (anfd->wev != wev)
382			{
383			method_modify (fd, anfd->wev, wev);
384			anfd->wev = wev;
385			}
386			}
387
388			fdchangecnt = 0;
389			}
390
391			static void
392	root	1.1	call_pending ()
393			{
394			int i;
395
396			for (i = 0; i < pendingcnt; ++i)
397			{
398			ANPENDING *p = pendings + i;
399
400			if (p->w)
401			{
402			p->w->pending = 0;
403			p->w->cb (p->w, p->events);
404			}
405			}
406
407			pendingcnt = 0;
408			}
409
410			static void
411	root	1.4	timers_reify (struct ev_timer **timers, int timercnt, ev_tstamp now)
412	root	1.1	{
413	root	1.4	while (timercnt && timers [0]->at <= now)
414	root	1.1	{
415			struct ev_timer *w = timers [0];
416
417	root	1.4	/* first reschedule or stop timer */
418	root	1.1	if (w->repeat)
419			{
420			if (w->is_abs)
421	root	1.4	w->at += floor ((now - w->at) / w->repeat + 1.) * w->repeat;
422	root	1.1	else
423	root	1.4	w->at = now + w->repeat;
424
425			assert (w->at > now);
426	root	1.1
427	root	1.4	downheap (timers, timercnt, 0);
428	root	1.1	}
429			else
430	root	1.4	{
431			evtimer_stop (w); /* nonrepeating: stop timer */
432			--timercnt; /* maybe pass by reference instead? */
433			}
434	root	1.1
435	root	1.10	event ((W)w, EV_TIMEOUT);
436	root	1.1	}
437			}
438
439	root	1.4	static void
440			time_update ()
441			{
442			int i;
443			ev_now = ev_time ();
444
445			if (have_monotonic)
446			{
447			ev_tstamp odiff = diff;
448
449			/* detecting time jumps is much more difficult */
450			for (i = 2; --i; ) /* loop a few times, before making important decisions */
451			{
452			now = get_clock ();
453			diff = ev_now - now;
454
455			if (fabs (odiff - diff) < MIN_TIMEJUMP)
456			return; /* all is well */
457
458			ev_now = ev_time ();
459			}
460
461			/* time jump detected, reschedule atimers */
462			for (i = 0; i < atimercnt; ++i)
463			{
464			struct ev_timer *w = atimers [i];
465			w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat;
466			}
467			}
468			else
469			{
470			if (now > ev_now \|\| now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
471			/* time jump detected, adjust rtimers */
472			for (i = 0; i < rtimercnt; ++i)
473			rtimers [i]->at += ev_now - now;
474
475			now = ev_now;
476			}
477			}
478
479	root	1.1	int ev_loop_done;
480
481	root	1.4	void ev_loop (int flags)
482	root	1.1	{
483			double block;
484			ev_loop_done = flags & EVLOOP_ONESHOT;
485
486	root	1.9	if (checkcnt)
487			{
488	root	1.10	queue_events ((W *)checks, checkcnt, EV_CHECK);
489	root	1.9	call_pending ();
490			}
491
492	root	1.1	do
493			{
494			/* update fd-related kernel structures */
495	root	1.5	fd_reify ();
496	root	1.1
497			/* calculate blocking time */
498	root	1.9	if (flags & EVLOOP_NONBLOCK \|\| idlecnt)
499	root	1.1	block = 0.;
500			else
501			{
502	root	1.4	block = MAX_BLOCKTIME;
503
504			if (rtimercnt)
505			{
506			ev_tstamp to = rtimers [0]->at - get_clock () + method_fudge;
507			if (block > to) block = to;
508			}
509
510			if (atimercnt)
511			{
512			ev_tstamp to = atimers [0]->at - ev_time () + method_fudge;
513			if (block > to) block = to;
514			}
515
516	root	1.1	if (block < 0.) block = 0.;
517			}
518
519			method_poll (block);
520
521	root	1.4	/* update ev_now, do magic */
522			time_update ();
523
524	root	1.9	/* queue pending timers and reschedule them */
525	root	1.4	/* absolute timers first */
526			timers_reify (atimers, atimercnt, ev_now);
527			/* relative timers second */
528			timers_reify (rtimers, rtimercnt, now);
529	root	1.1
530	root	1.9	/* queue idle watchers unless io or timers are pending */
531			if (!pendingcnt)
532	root	1.10	queue_events ((W *)idles, idlecnt, EV_IDLE);
533	root	1.9
534			/* queue check and possibly idle watchers */
535	root	1.10	queue_events ((W *)checks, checkcnt, EV_CHECK);
536	root	1.9
537	root	1.1	call_pending ();
538			}
539			while (!ev_loop_done);
540			}
541
542	root	1.8	/*****************************************************************************/
543
544	root	1.1	static void
545	root	1.10	wlist_add (WL *head, WL elem)
546	root	1.1	{
547			elem->next = *head;
548			*head = elem;
549			}
550
551			static void
552	root	1.10	wlist_del (WL *head, WL elem)
553	root	1.1	{
554			while (*head)
555			{
556			if (*head == elem)
557			{
558			*head = elem->next;
559			return;
560			}
561
562			head = &(*head)->next;
563			}
564			}
565
566			static void
567	root	1.10	ev_start (W w, int active)
568	root	1.1	{
569			w->pending = 0;
570			w->active = active;
571			}
572
573			static void
574	root	1.10	ev_stop (W w)
575	root	1.1	{
576			if (w->pending)
577			pendings [w->pending - 1].w = 0;
578
579			w->active = 0;
580			}
581
582	root	1.8	/*****************************************************************************/
583
584	root	1.1	void
585			evio_start (struct ev_io *w)
586			{
587			if (ev_is_active (w))
588			return;
589
590			int fd = w->fd;
591
592	root	1.10	ev_start ((W)w, 1);
593	root	1.1	array_needsize (anfds, anfdmax, fd + 1, anfds_init);
594	root	1.10	wlist_add ((WL *)&anfds[fd].head, (WL)w);
595	root	1.1
596			++fdchangecnt;
597			array_needsize (fdchanges, fdchangemax, fdchangecnt, );
598			fdchanges [fdchangecnt - 1] = fd;
599			}
600
601			void
602			evio_stop (struct ev_io *w)
603			{
604			if (!ev_is_active (w))
605			return;
606
607	root	1.10	wlist_del ((WL *)&anfds[w->fd].head, (WL)w);
608			ev_stop ((W)w);
609	root	1.1
610			++fdchangecnt;
611			array_needsize (fdchanges, fdchangemax, fdchangecnt, );
612			fdchanges [fdchangecnt - 1] = w->fd;
613			}
614
615			void
616			evtimer_start (struct ev_timer *w)
617			{
618			if (ev_is_active (w))
619			return;
620
621			if (w->is_abs)
622			{
623	root	1.2	/* this formula differs from the one in timer_reify becuse we do not round up */
624	root	1.1	if (w->repeat)
625			w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;
626	root	1.4
627	root	1.10	ev_start ((W)w, ++atimercnt);
628	root	1.4	array_needsize (atimers, atimermax, atimercnt, );
629			atimers [atimercnt - 1] = w;
630			upheap (atimers, atimercnt - 1);
631	root	1.1	}
632			else
633	root	1.4	{
634			w->at += now;
635
636	root	1.10	ev_start ((W)w, ++rtimercnt);
637	root	1.4	array_needsize (rtimers, rtimermax, rtimercnt, );
638			rtimers [rtimercnt - 1] = w;
639			upheap (rtimers, rtimercnt - 1);
640			}
641	root	1.1
642			}
643
644			void
645			evtimer_stop (struct ev_timer *w)
646			{
647			if (!ev_is_active (w))
648			return;
649
650	root	1.4	if (w->is_abs)
651	root	1.2	{
652	root	1.4	if (w->active < atimercnt--)
653			{
654			atimers [w->active - 1] = atimers [atimercnt];
655			downheap (atimers, atimercnt, w->active - 1);
656			}
657			}
658			else
659			{
660			if (w->active < rtimercnt--)
661			{
662			rtimers [w->active - 1] = rtimers [rtimercnt];
663			downheap (rtimers, rtimercnt, w->active - 1);
664			}
665	root	1.2	}
666
667	root	1.10	ev_stop ((W)w);
668	root	1.1	}
669
670			void
671			evsignal_start (struct ev_signal *w)
672			{
673			if (ev_is_active (w))
674			return;
675
676	root	1.10	ev_start ((W)w, 1);
677	root	1.1	array_needsize (signals, signalmax, w->signum, signals_init);
678	root	1.10	wlist_add ((WL *)&signals [w->signum - 1].head, (WL)w);
679	root	1.7
680			if (!w->next)
681			{
682			struct sigaction sa;
683			sa.sa_handler = sighandler;
684			sigfillset (&sa.sa_mask);
685			sa.sa_flags = 0;
686			sigaction (w->signum, &sa, 0);
687			}
688	root	1.1	}
689
690			void
691			evsignal_stop (struct ev_signal *w)
692			{
693			if (!ev_is_active (w))
694			return;
695
696	root	1.10	wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w);
697			ev_stop ((W)w);
698	root	1.7
699			if (!signals [w->signum - 1].head)
700			signal (w->signum, SIG_DFL);
701	root	1.1	}
702
703	root	1.9	void evidle_start (struct ev_idle *w)
704			{
705			if (ev_is_active (w))
706			return;
707
708	root	1.10	ev_start ((W)w, ++idlecnt);
709	root	1.9	array_needsize (idles, idlemax, idlecnt, );
710			idles [idlecnt - 1] = w;
711			}
712
713			void evidle_stop (struct ev_idle *w)
714			{
715			idles [w->active - 1] = idles [--idlecnt];
716	root	1.10	ev_stop ((W)w);
717	root	1.9	}
718
719			void evcheck_start (struct ev_check *w)
720			{
721			if (ev_is_active (w))
722			return;
723
724	root	1.10	ev_start ((W)w, ++checkcnt);
725	root	1.9	array_needsize (checks, checkmax, checkcnt, );
726			checks [checkcnt - 1] = w;
727			}
728
729			void evcheck_stop (struct ev_check *w)
730			{
731			checks [w->active - 1] = checks [--checkcnt];
732	root	1.10	ev_stop ((W)w);
733	root	1.9	}
734
735	root	1.1	/*****************************************************************************/
736	root	1.10
737			#if 0
738	root	1.1
739			static void
740			sin_cb (struct ev_io *w, int revents)
741			{
742			fprintf (stderr, "sin %d, revents %d\n", w->fd, revents);
743			}
744
745			static void
746			ocb (struct ev_timer *w, int revents)
747			{
748	root	1.4	//fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
749			evtimer_stop (w);
750			evtimer_start (w);
751	root	1.1	}
752
753	root	1.7	static void
754			scb (struct ev_signal *w, int revents)
755			{
756			fprintf (stderr, "signal %x,%d\n", revents, w->signum);
757			}
758
759	root	1.9	static void
760			gcb (struct ev_signal *w, int revents)
761			{
762			fprintf (stderr, "generic %x\n", revents);
763			}
764
765	root	1.1	int main (void)
766			{
767			struct ev_io sin;
768
769			ev_init (0);
770
771			evw_init (&sin, sin_cb, 55);
772			evio_set (&sin, 0, EV_READ);
773			evio_start (&sin);
774
775	root	1.4	struct ev_timer t[10000];
776	root	1.2
777	root	1.9	#if 0
778	root	1.2	int i;
779	root	1.4	for (i = 0; i < 10000; ++i)
780	root	1.2	{
781			struct ev_timer *w = t + i;
782			evw_init (w, ocb, i);
783	root	1.4	evtimer_set_abs (w, drand48 (), 0.99775533);
784	root	1.2	evtimer_start (w);
785			if (drand48 () < 0.5)
786			evtimer_stop (w);
787			}
788	root	1.4	#endif
789
790			struct ev_timer t1;
791			evw_init (&t1, ocb, 0);
792			evtimer_set_abs (&t1, 5, 10);
793			evtimer_start (&t1);
794	root	1.1
795	root	1.7	struct ev_signal sig;
796			evw_init (&sig, scb, 65535);
797			evsignal_set (&sig, SIGQUIT);
798			evsignal_start (&sig);
799
800	root	1.9	struct ev_check cw;
801			evw_init (&cw, gcb, 0);
802			evcheck_start (&cw);
803
804			struct ev_idle iw;
805			evw_init (&iw, gcb, 0);
806			evidle_start (&iw);
807
808	root	1.1	ev_loop (0);
809
810			return 0;
811			}
812
813			#endif
814
815
816
817